Sunday, December 2, 2007

Bullock's Oriole, and female oriole i.d.

[Top to bottom: Male Bullock's Oriole portrait; next two - same bird in acrobatic poses; bottom, one of at least three female Baltimore Orioles keeping company with the Bullock's. All photos around 2:15 p.m. Saturday, December 1, Bayshore Road. Click to enlarge; photos by Don Freiday].

On Paul Lehman's advice, I went to see the Bullock's Oriole in the early afternoon yesterday, rather than try for it in the morning, and other birders, including Gail Dwyer, were already on it.

Early afternoon seems to be the time to go after the bird, probably because the sun comes around to the south and lights up the little thicket where the bird has been hanging around. From the Beanery, go north on Bayshore Road to mile marker 1. There is an obscure Wildlife Management Area sign on the left (west) side of the road, where a grassy path goes west. We saw the bird right from the road, in the company of several female Baltimore Orioles, as well as Gray Catbirds, and Brown Thrasher. A Fox Sparrow and Yellow-bellied Sapsucker were nearby.

This is truly a gorgeous bird. When I first spoke to Paul about the discovery, he went on about where the bird was and when it was found, and only then casually dropped that it was a male and therefore "there was no need to be messing around when you see it," or something to that effect.

The "messing around" of course would be trying to distinguish a female Bullock's from a Baltimore, not always an easy task. Not ever an easy task, actually, but it can be done.

Considering the bottom photo, of one of the female Baltimore's, we should ask, why isn't this a Bullock's? Among the points to consider, note that this bird is brightest on the breast, with a duller malar and drab cheek. Female Bullock's are normally brightest on the malar and have bright cheeks. On this photo, we can also see the brownish scapulars with dark centers, characteristic of Baltimore. The back would be plain gray on a Bullock's. We also can see no sign of a dark eyeline, which should be evident on Bullock's, and that the greater coverts (the feathers whose tips form the lower wing bar) are pretty much dark except for the tips, without white edges. Finally, the median coverts (the feathers whose tips form the upper wingbar) do not have pointed dark centers, which is usually the way a Bullock's median coverts look - there is a jagged dark border on the upper side of the upper wingbar on Bullock's.

All this means that identifying female orioles is not a quick recognition thing; you need to see the bird well enough and long enough to collect all the information.

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